Cameras for three-dimensional measurement of objects using triangulation, as used, for example, for measuring teeth or imperfections in dental medicine, must be calibrated before the first use or even regularly. For this purpose, calibration sets, for example, are used that comprise a carrier on which markers are arranged in precisely known positions. For calibration, this calibration target, i.e., the carrier with the markers, can be positioned and captured in various positions relative to the camera. The camera is calibrated using the image and the precisely known positions of the markers on the carrier or relative to each other.
Because the positions of the markers on the carrier can fluctuate somewhat for reasons relating to production and the positions of the markers are therefore not known with sufficient precision to perform a proper calibration, each of the calibration sets is usually measured precisely before they can be used and the results are stored in a database.
If a calibration set is used to calibrate a camera, the precise positions of the markers can be checked in the database in advance, for example, using a serial number of the calibration set.
However, reading, entering or searching for the serial number or any other identification/code in the database is a source of error.
The object of the present invention is to avoid this source of error.